Self-venting fill cap for tank bodies



Feb. 16, 1954 w. v. BROWN ET AL SELF-VENTING FILL CAP FOR TANK BODIES Filed Maron 14, 1952 i '7 Sheets-Sheet 1 N .om

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sELF-vYENTrNG FILL CAP FOR TANK Booms Filed March 14, 1952 7 Sheets-Sheet 2 M4715?? I/ BROWN lA/APRE/v f" LOGEMA/v/v ATTORNEYS Feb. 16, 1954 Filed March 14, 1952 w. v BROWN ET AL SELF-VENTIG FILL CAP FOR TANK BODIES 7 Sheets- Sheet 3 HG. J'

JNVENToRs I/I/ALTER V. RoW/v MMP/@EN /f' LOGEMANN 5w www ATTORNEYS Feb. 16, 1954 w. v. BROWN ET AL 2,669,250

SELF-VENTING FILL CAP FOR TANK BODIES A Filed March 14, 1952 '7 Sheets-Sheet 4 INVENTORS l/l/ALTER l/ BROWN VIM/@REN LOGE/WANN A T TOR/vars Feb. 16, 1954 w. v. BRowN ET Al.

SELF-VENTING FILL CAP FOR TANKBODIES Filed March 14, 1952 7 Sheets-Sheet 5 "alla Hc. IO

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Feb 16, 1954 w. v. BROWN ETAL SELF-VENTING FILL CAP FOR TANK BODIES Filed March 14, 1952 NN n WM M mmM m5@ W mV/O +A TN R www 5 Feb. 16, 1954 w. v. BROWN ET Al.

SELF-VENTING FILL CAP FOR TANK Bonnes 7 Shee-ts-Sheet 7 Filed March 14, 1952.`

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Patented eb. 16, 1954 SELF-VENTING FILL CAP FOR TANK BODIES Walter V. Brown, Minneapolis, and Warren F. Logemann, St. Paul, Minn., assignors to Brown Steel Tank Company, Minneapolis, Minn., a corporation of Minnesota Application March 14, 1952, Serial No. 276,634

This invention relates to new and useful improvements in tank bodies and more particularly to truck or mobile tanks adapted for the transportation of iiuids such as oil and gasoline, or other fluids of a highly inammable nature.

Mobile tanks used for transporting gasoline and such materials from one place to another usually comprise a plurality of compartments or chambers which may or may not be intercon-V nected. When these compartments are independent of one another, each has a ll opening, usually located on top of the tank, and .each ll opening has a suitable closure or iill cap. In the past it has been customary to iill the tank compartments through theusual iill `openings provided on top of the tank. .This has been found objectionable and hazardous, iirjst,y Abecause it requires that an attendant or'` the operator must climb up on the tank and manually open each fill cap and position the loading arm or nozzle in lling relation thereto. As the compartments are successively filled, the operator closes each ll opening by manually securing .th ll caps to their respective seats.

Secondly, when directing the liquid into each compartment from the usual loading arm or nozzle at the bulk storage station, atmospheric air is entrained with the liquid and at the same time the liquid may be so agitated in the tank that when a high volatile liquid such as gasoline is being delivered into 'the tank, considerable loss of liquid may result from evaporation. The filling operation mayalso be extremely hazardous because of the highly inflammable nature of the vapor which may issue from the ll opening in the tank compartment during the'l'ling operation,I caused by the turbulence of the liquid in' the tank, it being understood that the liquid' is usually delivered into each compartment under pressure. Spillage of the highly inammable liquid may also occur which mayv result inA a serious explosion and fire, vWith a r sultantV loss of life and'pro-perty. v

To overcome the objections. above referred to, attempts have heretofore been made to ull the individual compartments of a truck tank from the bottom thereof, Which hask necessitated that each compartment be properly vented at the top 14 Claims. (Cl. IS7-267) cri 2 usually been quite complicated and expensive to install and maintain, and has not been Wholly vautomatic in operation. Y

It is therefore highly desirable that means be provided for venting the upper portions of the tank compartments, which means may be embodied in the construction of the usual ill cap and its mounting, and whereby the ll caps of all of the compartments of a given tank may be quickly and conveniently released from their respective seats, when the filling operation is started, thereby to permit the atmospheric air Within each compartment to freely escape therefrom as the. compartments are successivelyv and simultaneously nlled from the bottoms thereof. An important object of the present invention, therefore, is to provide a novelmechanism forventing theuppel portions of the various compartments of a truck tank, which mechanism may readily be embodied in the usual mounting means of the fill caps, and which operates to automatically eiect the release of the fill caps from their respective seats, each time liquid is initially introduced into the tank compartments, whereby the atmospheric air Within said compartments may freely escape therefrom during the iilling operation and Without requiring an attendant or operator to climb onto the tank to manually manipulate the venting means.

A further object is to provide a novel mechanism for automatically releasing each lill cap from its seat by fluid pressure, the instant liquid flow is introduced into one or more of the tank compartments, said mechanism operating to automatically return the ll caps into sealingengagement with their respective seats, upon interruption of liquid now to the compartments, as when they have received their full supply.

A further and more specific object of the invention is to mount a master cylinder adjacent to the usual manifoldof the tank having'one end in communication with the manifold,.whereby when uid is initially delivered to the manifold, under pressure, in the operation of lling one or more of the tank compartments,y said fluid will enter the adjacent end of the master cylinder and actuate a piston mounted forre-l ciprocal movement therein, said piston having an operative connection with a relatively smaller piston mounted in a cylinder containing a suitable pressure fluid, said smaller cylinder having a conduit connecting it with a plurality of operating cylinders, one located at each ll cap, and eaCLhoperating cylinder having a piston therein operatively ccnnectedto the locking mechanism A further object is to provide a truck tank hav- :ri

ing a plurality of compartments therein, and each compartment being provided with a ll cap having means for normally locking them in closed positions, and a mechanism being operatively connected to said locking means for simultaneously automatically releasing all of said locking means each time the supply conduit is connected to the truck manifold and liquid flow is established therethrough to ll one or more of the tank compartments.

.A further object is Ito vprovide a mechanism for simultaneously releasing the ill caps from their respective seats when the tank compartments are to be filled, which mechanism comprises va single control element conveniently located adjacent to the drivers cab, or elsewhere on the tank truck, whereby the fill caps of a given truck tank may be quickly and simultaneously released from their seats to permit venting of the compartments during the filling operation, and whereby the ll caps may as readily be restored to sealing engagement with their respective seats, when the lling operation has been completed.

Other objects of the invention reside in the simple and inexpensive construction oi the vent- 5;

require the attention of an operator each time the 1" tank compartments are to be iilled or emptied.

Other objects of the invention and the means for their attainment will. be more apparent from the following description taken in connection with the accompanying drawings.

In the accompanying drawings there has been disclosed a structure designed to carry out the various objects of the invention, but it is to `be, understood that the invention is not confined to the exact features shown, as various changes may be made within the scope of the claims which follow.

In the drawings:

Figure 1 is a top view of a conventional trailer tank showing the invention embodied therein;

Figure 2 is a side view of Figure l.;

Figure 3 is an enlarged detail sectional vview substantially on the line 3-5 of Figure l, showing the arrangement of the master cylinder and piston and the operating cylinder and piston Acorbnected therewith;

Figure 4 is a plan View of .a portion o a' fdl cap, showing the operating mechanism connected thereto;

Figure 5 is a view looking at Figure 4 from the right hand end thereof; y

Figure 6 is a detail sectional view on the line 6-6 of Figure 4, showing the nll cap locking means in Operative position; p

Figure 'i' is a detail sectional view on the line 1-1 of Figure 1i, with the parts positioned as shown in Figure 6;

Figure 8 is a view corresponding to Figure 6, but showing the operating mechanism actuated to release the ll cap from its seat;

Figure 9 .is a detailed sectional View showing the operating mechanism positioned to positively lift the ll cap from its seat;

Figure l0 is a detailed sectional view similar to Figure 7 but showing the parts positioned as shown in Figure 9;

lFigure l1 is a View showing a slightly modiiied construction wherein the ll cap locking means i is electrically operated;

-Figure l2 is a detail sectional view substantially on the line {2---192 of Figure ll, showing the operf, ing or releasing the fill caps, shown in Figure 13.

In `the selected embodiment :of `the invention herein disclosed there is illustrated in Figures l and v2, for purposes vof disclosure, a conventional truck or trailer tank comprising an elongated Y. body '2 having 'a plurality of bulkhead-s 3, 4 and 5 therein `for dividing the :interior :of vthe wtanl; into a ,plurality of compartments 6, l., 8 'and respectively. These compartments are provided with means ,for introducing a yliquid fuel thereinto, and is here shown 'comprising a manifold il having a plurality of valves l2, 13, lll and I5, therein having conduits l5, il, i8 "and .is connecting them with the compartments yi5, :i and 9, respectively, as indicated by the dotted lines in Figure 1 In Figures 1 and 2 it will be noted the manifold IVI is located at .one sid/e of the tank body 2 and at an elevation below `the bottom of the tank whereby the compartments 6 l, 8 vand '9 are lled from the bottom. TThe manifold is .shown having a rearward :extension .2e provided with a vterminal vfitting 2l to which one end of .a conduit or hose, not shown, may be connected for emptying the tank compartments. A liquid measuring 'meter 22 and a .shut-off 'valve 22" are interposed on the extension 20 lfor measuring and controlling fuel flow fromthe compartments, as `is well known in 'the trade. The manifold H also has a 'forward extension 23 having a terminal iltting 2i similar to the one provided on .the rearward extension .20, to facilitate attaching a vconduit thereto. A measuring meter 24 and yshut-olf valve 24' .are .also provided in extension '2.3. A shut-oil valve '25 may .also be interposed between the lvalves I3 and 'i il, as illustrated 'in Figures 1 and v2.

'The manifold ll has a lateral extension 26 provided at its outer end with a suitable coupling 21 whereby a lling or loading conduit, not shown, may be `connected thereto for conducting `Iluid from ythe source of supply at the loading station to the various compartments of the tankbody. A valve. 26" is provided in the extension 26 `for controlling liquid new therethrough.

The arrangementof valves i2 to i5, inclusive, and 22', 24", 25 and 25 in the manifold H is such that all cf'compartments may be filled at one time or, if desired, they may be iilled one at a time.

When filling the tank compartments from` their` bottoms, as herein disclosed, it is essential that means be provided for venting each compartment to allow atmospheric air therein to escape therefrom, as the level of the liquid rises therein during the filling operation. To thus Vent the various tank compartments constitutes an important feature of the present invention. As herein disclosed, al'l of the fill caps 28 of compartments 6, 1, 9 and 9, respectively, are vented simultaneously, the instant the flow of liquid into one or more of the compartments is initiated, and such venting is accomplished automatically by the pressure of the fluid introduced into the manifold I for distribution to the various compartments. To thus automatically break the seal between each ll cap and its seat, means is provided for automatically actuating the locking means for the l'l caps, which will next be described.-

As best illustrated in Figures '1 and 10 each ll cap 28 is shown having its central portion operatively connected to a member 29 pivoted at A3| to a lug or projection 32 provided upon the usual collar 33 which defines the ll opening of each' Figure 7, the gaskets 35 thereof will sealingly engage their respective seats 34 to prevent leakage of gaseous fumes or vapors from the various compartments of the tank body.

A locking lever 36 has a convex portion 31 at one end adapted to be received in a concave seat 38 provided in the opposite end of the pivoted member 29, as shown in Figure 7. A pluralityof U-shaped spring elements 39 have their corresponding ends pivotally connected to the locking lever 36 by a pivot pin 4|, and the opposite ends of said spring elements are pivoted to the lower arms 42 of a plurality of bellcranks 43 by pivot pins 44. 'I'he bellcranks 43 are secured to a rockshaft 45 supportedl in spaced apertured lugs 46 secured to the collar 33 of the fill openingand the top wall 41 of the tank. The bellcranks 43 are tied together for simultaneous operationby an elongated bar 49 which, to facilitate manufacture, may be cast integral with the bell element 43, as will be understood by reference to Figures 4 and 7.

The pivots 4|, 44 and 45 are so disposed relative to one another that when the bar 49 isin the position shown in Figure '1, the lower pivot 44 has passed over a line a-a drawn through the axes of pivots 4| and 45, or to an over-the-center position relative to pivots 4| and 45, whereby the spring elements are placed under tension to retain the fill caps 26 in sealing engagement with their respective seats 34 through the locking lever 36, as will readily be understood by reference to Figure 1. To open a i'lll cap, its locking lever 36 may be swung upwardly and rearwardly as indicated by the dotted' lines in Figure '1, whereby the pivoted member 29 `is released and may be swung upwardly to lift the ll cap from its seat, as is well known.

To automatically release the iill caps from their seats to permit atmospheric air to escape from the compartments being lled, means is provided for imparting a rocking motion to the pivot pins or shafts 45 as soonas the filling operation'y is started, and'whereby the operating member or tothe position shown inFigure l0' when so positioned, the .gaskets 35 of the fill caps are partially lifted from their seats to provide vent openings through which the air within the compartments may readily escape to the atmosphere during the filling operation.

The means provided for thus automatically actuating the bellcranks 43 to release the fill caps from their respective seats is shown comprising a, master cylinder 5| having heads 52 and 53 secured to the ends thereof by suitable bolts 54. The heads 52 and 53 may be provided with legs 55 and 56, respectively, adapted to be secured to the bottom wall 51 of the side compartment 58 of the truck body which houses the manifold and control valves or apparatus, as illustrated'in Figures 1 and 2.

A piston 59 is mounted for reciprocal movement within the cylinder 5| and has a cupshaped gasket 5| secured thereto for preventing leakage of the pressure uid from the pressure chamber 62 provided in the cap 53. The cylinder head 53, it will be noted by reference to Figure 3, is provided with suitable spacing lugs 63 adapted to engage the adjacent end of piston 59 to space it from the head 53 so that the pressure fluid introduced into the pressure chamber 52 may contact the entire end area of piston 59. A conduit 64 has one end secured in the head 53 and is in communication with the chamber E62. The opposite end of the conduit S4 is connected to the extension 26 ofv the manifold, whereby when uid under pressure is delivered into extension 26 from the loading hose or conduit, a portion of said fluid will enter chamber 62 of the master cylinder 5| and thus force its piston 59 towards the opposite end of the cylinder. l Secured to the cylinder head 52 at the opposite end of the master cylinder 5| is a relatively smaller operating cylinder 65 having a head 66 secured to its outer end, as clearly illustrated in Figure 3. A suitable spring 61 is mounted within the cylinder 65 and has one end seated against the head 66 and its opposite end against a cup-shaped gasket 68 fitted against the end of a piston 69 mounted for reciprocal movement within cylinder 65. Piston 39 is secured to piston 59 by aconnecting rod 1|, whereby the two pistons are adapted for simultaneous operation when uid is introduced into the chamber 62 o fthe master cylinder. An air vent 12 is shown' provided in the head 52 of the master cylinder to prevent the formation of a back pressure or vacuum therein, when piston 59 is reciprocated' in cylinder 5|. A suitable lter material 13 is provided in the air vent 12 to prevent foreign matter' from enteringv therethrough into cylinder 5|. y

Connected to the head 66 of the operating cylinder 65 is one 'end of a conduit 14, the opposite end of which is connected to a cylinder head 15 secured to one end of a small cylinder 1e which is shown supported by a rsplit bracket, generally designated by the numeral 11. The bracket 11, it will be noted by reference to Figure` 4, may be secured to one of the longitudinally extending overturn protection rails 18 provided on top of the tank, as kshown in Figures l, 4 and 5. The cylinders 16 are secured in position in brackets 11 by suitable bolts 19.

Each cylinder 16 has a piston 8| therein to which one end of a connecting rod 82 is suitably secured, the' opposite end of each connectingl rod is preferably forked, as shown at 8 3 in Figure Il,v and is pivoted to an arm 84 by a pin 85." Armr 841s ,nxedly secured to a rock-shaft 45 having` one. end secured to the pivot shaft or rod 45r to` which the bellcranks 43 are. secured` The. opposite end of shaft 45 is rotatively supported in a bearing 81 secured tol the top rail 1B, as will be understood by reference to Figure 4.

`A second arm 88 is secured to the rock-shaft 45 and has. one end of a spring 89 secured thereto, the opposite end, of which is attached to a fixed bracket 9i which may be secured to the top rail 18, as. shown in Figurev 4. The spring 89y constantly exerts a force on the arm 88 to rock the shaft 45., and therefore the operating member 48 in a counter-clockwise direction, when viewed as shown. in Figures 6, 8 and 9, thereby to normally retain the fill cap in sealtight engagement with its seat 34.

In operation, cylinders l and 65, conduit 1.4., and all cylinders 16 are filled with a suitable inelastic pressure fluid so that each time .liquid fuel enters chamber 52` of the master cylinder from loading extension 2t, such liquid fuel will cause the-piston 5S of the master cylinder, and also the piston 69 in the operating cylinder 65 to move in. a direction towards the left, when viewed as shown in Figure 3. Such movement of pistons 59 and 59 will force the liquid or fluid in conduit 14 into cylinders. lt,A whereby the pistons 8| thereof are simultaneously actuatedto partially rotate all rock-shafts 45 and thereby automatically release the nll caps from their respective seats, as will be readily understood by reference to Figures 9 and 10. Conduit i4 preferably leads from the operating cylinder B5 directly to the cylinder 16 of the foremost ill cap 23, and the cylinders 'I6 of the remaining ll caps have branch conduits 92 connecting them to conduit 14, as illustrated in Figure l. A vent plug S3 is preferably provided in the cylinder head of each cylinder It to release therefrom any air which may be entrapped therein with the pressure fluid, when initially introduced into the closed system.

The apparatus above described, and as illustrated in Figures 1 and 2 operates in the following manner: when it is desired to ll one or more of the compartmentsy 6, l, 8 and 9, the loading hose at the bulle storage plant is. connected to the tting 21 of the lateral extension 25, and the shut-off valve 25 may then be opened to permit the liquid fuel to enter manifold H. If the two rearward compartments and 1 are to be filled with a certain kind of liquid fuel, valves I2 and I3 are opened to permit the fuel to. flow through conduits I6 and il to their respective compartments 6 Aand 1. The liquid fuel is delivered to the lateral extension 25 under pressure, and as the chamber 52 of the master cylinder 5| is in direct communication-with the lateral extension 26 through the conduit 64, the fluid will enter chamber 52 and move the piston 59 in the direction indicated by the arrow in Figure 3, whereby the piston 59 of the operating cylinder 6l is moved toward the head 65 of said cylinder against the compression of the spring El.

y Such movement of piston 53 by piston 55 will cause the fluid in cylinder 55 to be forced through conduit 'i4 and into each of the relatively smaller cylinders 'l5 of the four ll caps at the tcp of the tank. As the fluid is` thus forced into cylinders 16 the pistons 8l thereof are actuated to partially rotate shafts of the flll caps and thereby actuate the bellcranks 43 to release the tension in they-#shaped springs 39 of each ll cap, whereby thell caps may readily be lifted oit their. seats 34 when the members 49 engage the edges of their respective fill caps', as. shown in Figure 10. When the `fill caps are thus positioned, air within the compartments may readily escape therefrom through the gaps provided between the seat 34 and gasket 35 of each Jll cap, as will readily be understood.

As. long as liquid fuel is flowing through the lateral extension 26 of the tank compartments, the. piston 59 of the master cylinder 5l is retained in the dotted line position shown in Figure '3, whereby the pistons 8l. of the cylinders 'i5 of the fill cap locking mechanisms are retained in the positions shown in Figure 9, wherein itv Will be noted that the lill caps 26 are retained in open position. See also Figure 10.

When the compartments. being filled have received their full charge or load, shut-off valves l2, I3 and 26" may be closed and the loading conduit may then be detached from the lateral extension 25.. Such interruption of uid flow through eX- tension 293 releases the fluid pressure against piston 59, whereupon spring El restores piston to its normal position, shown in full lines in Figure 3, assisted by the springs B of the relatively smaller' cylinders l5. The pistons 8l of cylinders 'i5 are simultaneously returned to their normal positions, shown in Figure 6, and at the same time the U- shaped springs 39 are placed under tension to retain the fill caps 28v in sealing engagement with their respective seats, as will readily be understood by reference to Figure r7. In this ligure it will be noted the lower pivots 44 of the springs 33 of each fill cap, have passed over the line a-a drawn through the axes of pivots 4l and 45, whereby the ll caps are rmly locked to their seats to prevent any possible danger of leakage from the. ll openings.

From the foregoing, it will be noted that the venting of the fill caps is completely automatic, and is accomplished entirely by the pressure oi the liquid fuel. flowing, through the extension 25 to the tank compartments being filled, through the medium of the master cylinder 5|. The forward compartments. 8 and 9 may be filled in identically the same manner as the rear compartments 5 and 1, by manipulation of valves i4, l5 and 25.

When the contents of the tank compartments 6, l, 8 and 9 are to be discharged therefrom into a suitable receiving tank or tanks, one end of a suitable hose is connected to one or the other of the ttings 2I provided at the ends of the drain extensions 20 and 23, and the proper valves are .l then manipulated to permit liquid fuel to drain from the compartments to be emptied. As the liquid fuel flows from the tank compartments, it passes through one or the other of the two measuring meters 22 or 24, which record the number of gallons delivered into the receiving f tank. Suitable doors 90, shown in Figures 1 and 2, are provided for closing the side chamber in the truck body where the control valves and manifold are disposed, as will be understood.

Figures l1 and 12 illustrate a slightly modied construction wherein electrical means is provided for simultaneously releasing the fill caps 28 from their respective seats for the purpose of venting the compartments during the lling or emptying operations. As schematically illustrated in Figure. 11, a solenoid, generally designated by the numeral 94, is mounted at some suitable location on the truck body and has ar movable. element 55 ,therein to which one end of a connecting rod 9S is attached, 'as best illustrated in Figure 12. The opposite end of connecting rod 06 is pivotally connected to the forward end of an elongated bar 91 by a suitable pivot pin 98. In the form shown in Figures 11 and 12, the rock shafts 45 of the locking mechanisms of the fill caps each have an arm 99 secured thereto which correspond to the arms 84 of the form shown in the previous gures.

The arms 99 are pivoted to the bar 91 by pivot pins whereby all of the rock-shafts of the fill caps are simultaneously operated when the bar 91 is actuated by the solenoid 94. The bar 91 is normally retained in its forward position to secure the ll caps in their closed positions by suitable lsprings |02, similar to the springs09 of the previous figures. Springs |02 each have one end Vconnected to an arm 88 provided on the rockshafts 45, and the opposite ends of said springs are secured to fixed brackets |03 whereby all springs |02 cooperate to constantly urge the lock- -ing mechanisms into operative positions to secure the ll caps in leaktight engagement with their respective seats 34, as shown in Figures 6 and 7.

The solenoid 94 has an electric circuit |04 which is shown connected to the usual battery |05 of the truck. A suitable control switch |00 is provided in the circuit |04 and may be located at any convenient location on the vehicle as, for example, in the drivers cab, or in the side compartment which houses the various control valves, illustrated in Figures 1 and 2.

The'mechanism illustrated in Figures 11 and 12 operates as follows: normally the operating bar `91 is in its forward position whereby the ll caps are secured in closed positions as illustrated in Figures 6 and 7. When it is desired to release the fill caps from their respective seats to vent the fuel compartments, the switch |06 is closed, whereupon the movable element 95 of the sole noid, which normally is retracted, is thrust outwardly and thereby rearwardly moves the operating bar 91 through the connecting rod 96 and thus effects operation of the bellcranks 43 of the ll caps. Such operation of bellcranks 43 will cause members 49 of the bellcranks to swing into engagement with the pivoted members 29 of the iill caps, as shown at B in Figure 10, and thereby temporarily lock the fill caps in partially open positions.

When the fuel compartments of the truck tank have been filled or emptied of their contents, the operator opens switch |06, whereupon the springs |02 cooperate to actuate the rock-shafts 45 and thereby again place the U-shaped springs 39 thereby to release the iill caps from their seats .and permit venting of the compartments, as in the previous gures.

The operating lever |01 is shown pivoted in a suitable bracket |09 and has one end of a connecting rod connected thereto, the opposite end of which is connected to one arm of a bellcrank ||2, pivotally mounted on the truck body. The

vopposite arm of bellcrank I2 is connected to the rlower end of a rod l I3, the upper end of which is connected to one arm of a bellcrank I4, the other arm of which is operatively connected to the forward end of the operating rod E08, Thus, it will be seen that when it is desired to vent the fuel compartments 0, 1, 8 and 9, the driver or operator simply swings the lever to the dotted line position, whereupon all of the lill caps are released and partially opened, as shown in Figure 10.

What we claim is:

1. The combination with a truck for transporting volatile liquids comprising an elongated tank body having a plurality of compartments therein, and the top wall of each compartment having an opening therein, and each of said openings having a closure which is normally secured in closed position by a locking mechanism, of a bottom-fill mechanism comprising a manifold having a plurality of conduits connecting it to the bottoms of said con'lpartments,` valves for selectively controlling liquid flow through said conduits, said manifold having a loading branch provided with means for detachably securing one end of a loading arm or hose thereto, the opposite end of which is connected to a source of liquid fuel under pressure whereby the tank compartments may be filled from their bottoms, under pressure, and a pressure responsive device in communication with said manifold for simultaneously effecting actuation of all of said locking mechanisms to release said top closures, when liquid iiow is established through said loading branch to ll one or more of said compartments, thereby to automatically vent said compartments during the filling operation.

2. An apparatus according to claim l, wherein the pressure responsive device comprises a closed chamber having a movable element therein, said chamber being in direct communication with said loading branch whereby a portion of the liquid fuel flowing through the loading branch to said compartments, during the filling operation, will enter said chamber and actuate said element to automatically effect the release of said top closures.

3. An apparatus according to claim 1, wherein the pressure responsive device for eecting actuation of said locking mechanisms includes interconnected operating and master cylinders, the master cylinder being in direct communication with said manifold.

4. The combination with a truck tank forV transporting volatile liquids comprising an elongated tank body having a plurality of compartments therein each provided with a vent opening in its top wall, a closure for each of said openings, and means for normally locking said closures in closed positions, of a bottom-fill mechanism comprising a manifold having a plurality of conduits connecting it to the bottoms of said compartments, valves for controlling liquid flow through said conduits, said manifold having a loading branch provided with means for detachably securing one end of a loading arm or hose thereto, the other end of which is in communication with a liquid supply under pressure, said top closure locking means being inter-connected, and a hydraulically operated device in communication with said loading branch and having an operative connection with said locking means, whereby when liquid fuel is direct-ed through said loading branch to the manifold, a portion thereof will enter said device and automatically effect actuation of said locking means and thereby release said top closures to vent the compartments during the filling operation.

5. A truck tank for transporting volatile liquids comprising an elongated tank body having a plurality of compartments therein each provided with an opening in its top wall, a closure for each of Asaid openings, fluid operated means for nor'- mally locking said closures in closed positions, a manifold having a plurality of conduits connect'- ing it to the bottoms of said compartments, valves for selectively controlling liquid flow through said conduits, said manifold having a loading branch provided with means for detachably securing one end of a loading arm or hose thereto, the other end of which is in communication with a liquid supply under pressure, said top closure locking means being inter-connected for simultaneous operation, an enlarged master cylinder having one end in communication with said loading branch and having a piston therein, a relatively smaller cylinder axially aligned With said master cylinder and having a piston therein operatively connected to the piston in the master cylinder for direct movement therewith, a pressure fluid in said smaller cylinder, and a conduit connecting said smaller cylinder with the uid operated locking means of said top` closures, whereby when liquid fuel is directed through said loading branch to the compartments, a portion thereof will enter the master cylinder and actuate said pistons, whereby a portion of the pressure fiuid in said smaller cylinder is forced into the conduit connecting it to said iluid operated locking means, whereby said means are actuated to automatically effect the release of saidtop closures to permit air entrapped insaid compartments to escape therefrom during the filling operation.

6. In a truck tanl: having a plurality of compartments, a manifold disposed at an elevation substantially below said compartments, conduits for establishing communication between said compartments and the manifold, valvesl for selectively controlling liquid flow from the manifold to the compartments, a vent opening in the upper portion of each compartment each having a closure, means for normally retaining said closures in closed` position, an operating device for each closure retaining means, each including a movable element, said manifold vhaving a loading branch provided with means for attaching thereto one end of a flexible loading conduit for supplying liquid fuel to the manifold under pressure, and a pressure responsive element in communication with said loading branch and having operative connections with the movable elements of said closure retaining means, whereby when liquidy fuelY is directed through the loading branch to the manifold, said pressure responsive element is actuated by iiuid pressure to automatically effeet the release of said vent closures to permit venting of the Ycompartments during the filling operation.

7. In an apparatus according to claim 6, wheren means is provided for automatically closing said vents when fluid iiow through said loading branch to the compartments is interrupted.

`8. In a truck tank having a plurality of comfpartments, a manifold disposed at an elevation below said compartments, conduits for establishing communication between said compartments and the manifold, valves for selectively controlling liquid iiow from the manifold to the compartments, a vent opening in the upper Wall `of each compartment each having a closure, a mechanism for normally locking each vent clo'- sure in closed position, each comprising a rockshaft, spring means operatively connecting said rockshafts with their respective closures and op.- crating to normally retain the closures in sealing engagement with their respective seats, an operating device for each rockshaft, including a movable element having an operative connection with its respective rockshaft, said manifold having a loading branch provided with means rfor attaching thereto one end of a iiexible vloading conduit for supplying liquid Afuel to the manifold under pressure, and Va pressure responsive elementv in communication with said loading branch and having operative connections with the movable elements or said closure locking mechanisms, whereby when liquid fuel is directed through the loading branch to nil one or more of said compartments, said pressure responsive element is actuated by fluid pressure to operate the movable elements of said mechanisms and automatically effect the release of said vent closures to permit venting of the compartments during the lling operation.

9 In an app-aratus 'according to claim 8, Wherein the operating devices for the closures of said vents 'are duid-operated to open the vents, and spring means is provided for automatically closing said vents when iluid flow through the loading branch. to the compartments is interrupted.

10. A truck tank for transporting volatile liquids comprising an elongated tank having a plurality of compartments therein, va combination nil opening and vent in the upper wall of each compartment, i'lll caps for said openings, an operating member for each fill rcap having operative connections with the central portions of their respective ll caps, means for norm-ally llocking said operating members in iill-cap sealing positions, each locking means comprising a rockshaft having an arm secured thereto and depending therefrom and having one endl of a resilientl element pivoted theretdthe othery ends of said resilient elements having pivotal connections with their respective fill caps above said rockshafts Whereby said resilient elements are normally under tension to secure the ll caps to their seats, elongated elements movableA with said arms to engage their respective iill-cap operating members and partially unseat the lill caps, when' said arms 'are actuated, a second arm secured to each rockshaft,v and an elongated bar pivotally connected to saidj second arms and adapted, upon movement in one direction, to simultaneously partials ly rotate said rockshafts to release the Atension in said resilient elements and thereby effect the release of the iill caps from their respective seats and permit them -to open to vent said compartments.v

11. A 'truck tank according to claim 10, Wherein a single operating device is provided for actuatingV said elongated bar to effect the release of the iill caps from their respective seats.

12. A truck tank according to claim 10, Wherein electricl means is provided for operating said elongated bar to simultaneously effect the release o f the ll `caps from their seats.

13. A combination bottom-lill and vent mechanism for a multiple compartment 'liquid fuel tank having a top Wall, an opening in 'said wall for each compartment and each openingfhaving la seat, a hinged closure for eachopening, means normally locking said closures in sealing engagement with their respective seats, each locking means comprising a rockshafthaving a depending arm secured thereto and Aa U-shaped spring element having one end pivoted to the llower end of said arm, the other ends of said spring ele- 13 ments being pivotally connected to their respective closures substantially directly above said rockshafts, whereby when said rockshafts are in closure sealing positions, the pivotal connections between said arms and spring elements are disposed in over-the-center positions relative to the axes of their respective rockshafts and pivotal connections with the closures, and whereby said closures are normally retained in Sealing engagement with their seats under spring tension, a manifold having a plurality of conduits connecting it to the bottoms of said comp-artments for conducting liquid fuel from the manifold thereto, valves for selectively controlling liquid flow from the manifold to said compartments, said manifold having a loading branch provided with means for detachably connecting one end of a exible loading conduit thereto for delivering liquid fuel thereto under pressure, a pressure responsive device having a chamber therein, a movable element in said chamber and defining a wall thereof, means for establishing communication between the loading branch and said chamber whereby the movable element in said chamber is under the direct influence of the pressure of the liquid fuel flowing delivered to the manifold, when loading or charging the tank compartments, and said pressure responsive element having an operative connection with the rockshafts of said closure locking means, whereby when liquid fuel is flowing through the loading branch to the manifold and compartments, said pressure responsive element is actuated by the pressure of the liquid fuel to simultaneously actuate said rockshafts to automatically release said closures from their respective seats to permit free venting of said compartments during the filling operation.

14. A combination bottom-fill and vent mechanism as dened in claim 13, wherein a member is secured to each rockshaft for positively lifting each closure from its seat, when said locking means are actuated to release the closures.

WALTER V. BROWN. WARREN F. LOGEMANN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 223,867 Snyder Jan. 27, 1880 2,037,020 Holby Apr. 14, 1936 2,096,374 Jensen Oct. 19, 1937 2,261,936 Johnson Nov. 11, 1941 2,430,956 Scott Nov. 18, 1947 

